Static charge eliminator



y 1950 w. c. HERBERT ETAL 2,514,864

STATIC CHARGE ELIMINATOR Filed Nov. 15, 1946 m/mmmm mnimnnmrm.

INVENTQIES.

WILL/AM CHEESE/3T iwa/wi ATTORNEY.

WILLIAM C. HERBERT, JR.

Patented July 11, 1950 STATIC CHARGE ELIMINATOR William Charles Herbert, Brooklyn, and William Charles Herbert, In, Freeport, N. Y.

JApplication'November 15, 1946, Serial No. 710,036,

3 Claims.

1 This invention relates to an electrical discharge device, and more particularly to an a tachment which can be conveniently installed ,for the elimination of charges of static electricity.

An important object of the invention is to provide a .static eliminator which can easily and quickly be mounted in operative position adjacent a machine which delivers a product made of paper or other sheet material in any form which collects static charges in the process of treatment; and which will act efiiciently to re- :move all suchcharges, so that the article which the machine turns out will be in a satisfactory condition, for handling when finished.

.Another object of the invention is to provide a static eliminator which has superior dielectric properties enabling .it to bear heavy electrical loads without risk of short circuit or breakdown of parts, .or any other damage; and which is nevertheless of comparatively simple construction, inexpensive .to produce, and very durable in actual service.

The drawings show the best embodiment of my invention now known to me, and the novel features of the improvement are defined in the appended claims. This disclosure, however, is explanatory only, and changes in structural details may of course be made without abandoning any of the essential, features which the invention contains.

In the drawings:

Figure 1 is a view showing a complete eliminator according to my invention, and the method of mounting the same'in operative position.

Figure 2 is a section through part of the eliminator, showing the internal construction and connections thereof to a supply circuit.

Figure 3 presents a detail of a modification,

Figure 4 shows a clamping bracket for mounting the eliminator in position on the framework of an apparatus which works upon sheet material that is apt to receive charges of static electricity in the process of manufacturing or finishingthe article for which it'isused.

The numeral l indicates a static'neutralizer bar carrying a plurality of short electrodes pro- 'j-ecting therefrom and arranged in a straight line at separatedpoints along the length thereof. The electrodes are indicated by the numeral 2-, and they are embedded in perforated nipples 3 which have threaded ends screwed into the bar I, and projecting beyond the electrodes 2. The ends of the electrodes are exposed through the outer ends of the perforations-or bores 4 in the nipples 3, but terminate within these bores.

The bar is designed to beenergized from a high tension step-up transformer 5, which is connected to an insulated terminal 6; the bar itself being con-nected by an insulated cable to a similar insulated terminal I. When the bar is to be charged, these two electrodes are bridged by a drop switch 8. To secure the bar in operative position with respect to the apparatus with which it is to be used, it is engaged by clamp 9 at both ends, these clamps being attached to suitable supports on the framework of said machine. The transformer receives alternating current.

The bar itself comprises a tubular casing l of insulator material with high dielectric strength, With threaded openings at various points to receive the ends of the hard rubber nipples 3. The nipples project past the electrodes 2, which are enveloped and the paper is thus protected from the sparks. Within the casing, protruding from one end, is a solid conductor rod or member ll, connected to a cable 12, made up of a wire or conductor enclosed in an insulator sleeve or sheath, the cable being enveloped over its entire length by a length of sheet rubber tubing [3. This rubber tubing is in turn enveloped by a tubular sleeve of brass 14, against which the rubber nippics 3 and the inner ends of the electrodes 2 abut. The rubber and brass tubes or sleeves l3 and M are closed at both ends over the cable I 2 by a suitable sealing composition l5. The rod it is soldered to the conductor in the cable 12. The cable is insulated heavily enough to withstand a breakdown test of 15,000 volts.

The rod l 5 passes at one end through a closure plug ll of insulation and of course it is similarly closed at the other end. The rod l i has threads 58 to receive a binding nut I9 screwed tightly against the plug ll to hold this plug in place. The end of the casing i is fitted into a head 20, which has a cylindrical recess or cavity 2! to receive the end of the casing l, and the head 28, of hard rubber, also has a central bore 22a run plug into it longitudinally from the bottom of the recess 2! to receive the smooth end of the rod H. This bore has a metallic lining or sleeve 23 into which the end of the central conductor rod it is inserted. The head also has a bore 22b at right angles to the bore 22a, and in this bore an element such as a conductor pin 24, having screw tln'eaded connection with the sleeve at its inner end and projecting from the side of the head at the other. The casing l is rotatable in the head to adjust the electrodes 2.

The head 23 is shown as being rounded, or cylindrical with the cavity ii at one end, and it also has a cavity or recess 25 in one side in line with the inner end of the bore 22a, receiving the rod II, and concentric with the pin 24, and into this recess is fitted a sleeve of hard rubber 26, which is attached to the cable joining the bar I to the insulated terminal 1. The sleeve 26 has a longitudinal bore extending into it from the end in the cavity 25; this bore being lined by a conductor sleeve 2? having a flange or expanded extremity 28 at the outer end to fit the countersunk outer end of the bore, and this sleeve 21 receives the connector pin or stud 24. The sleeve or lining 21 is thus put into electrical connection with the rod or element I I. The other end of the sleeve 26 has an enlarged bore in line with the bore having the lining 27 with a shoulder at the junction of the two bores and the inner end of the lining 2'1; and into this bore is inserted the insulated conductor 29 running to the terminal I. At the inner end of this cable is a threaded flanged screw 30, and the conductor wire 29 is inserted into an opening through this screw and soldered fast. The flange on this screw abuts the internal shoulder and the sleeve .21, and the cable has a covering 3! in gum rubber tubing 32.

The screw is attached to the end of the conductor 29 and then the cable with the screw thereon is inserted into the coupling sleeve 26 at one end, the sleeve or lining 2'! being inserted at the other. By turning the parts, the screw 38 screws into the lining 21. Then upon insertion of the sleeve 26 into the recess 25, the stud 2 enters the lining 2! and the connection of the conductor 29 to the bar l is complete. The cable made up of the conductor 29 and insulator 3| extends from the bar I to the terminal I.

The transformer can be attached to the ceiling or some other point, and the high tension cable 33 leading to the terminal 6 is supported by one ormore insulators 34. The two terminals 6 and l are mounted in insulated posts 35, attached to an insulator plate 38, fastened to the ceiling, for example, and bearing a casing 31 containing a magnetic coil to operate a plunger 38. This plunger is connected to a lever 39 pivoted on the casing 31, and the opposite end of the lever is connected by a link 4!! to one end of the switch bar 8, which is pivotally attached to the terminal 1. When the device is to be used, the switch in the supply circuit (not shown) of the magnetic coil in the casing 31 is closed. The

plunger is then pulled up and the link 49 swings the switch 8 to bridge the terminals 6 and 1. Thus the bar is connected to the transformer and is energized. The link 48 is necessarily of insulation.

If several of these eliminators are to be used, additional plates 36 with posts carrying terminals like the terminals 6 and l, and magnetic coils and switches like the bar 8 to close the circuit, will be employed. The additional apparatus will have a terminal corresponding to the terminal 6 connected by a conductor to the terminal 6 shown in Figure 1, and whenever its magnetic switch is actuated, this terminal will be connected to a terminal like the terminal l near it, which in turn is joined to a bar similar to the bar I.

The clamps for mounting the bar comprise a pair of arched gripping elements 6!, the ends of which are held together by screws 52 so that these clamps encircle and can be affixed to parts of the machine, for which the neutralizer is needed. One of these elements has a hollow boss 43 to receive a rod M, adjustably held by a binding screw 45. At the outer end of this rod or shank is a pivot stud 46, to which is pivotally attached the insulating block or arm 41 having an opening 48 therein to receive the bar I. The end of the insulator arm is split at 49 and a binding screw 50 in said end draws the split portions together to secure the insulator tightly to the bar I. The neutralizer bar can thus be supported in position with the nipples pointing toward the sheet of paper or the like, and will then operate as required. Preferably the bar 1 should be supported under the paper t give the best results, and as near to the source of static generation as possible. A nut 46a. on the threaded end of the stud 46 holds the arm 41 in correct position.

The electrodes carried by the static bar can either be of the form of the conductors 2 in nipples 3, which are in contact with the brass sleeve l 4, or they can be metallic studs 5! screwed into the outer sleeve of the bar abutting against the brass sleeve I l and flexible spring points 52 of coiled Wire which terminate in points, indicated in Figure 3. By the use thereof the spring points 52 are separately adjustable by bending same. These flexible points 52, being wound right hand are permitted to screw on studs 5i, but the spring tension prohibits their backing off under any kind of abuse. The extreme flexibility also completely offsets the possibilityof breakage from sudden blows, etc. The nipples are preferred in places Where gas or other combustible materials may be nearby.

Our eliminator, because of its high dielectric properties, will bear exceedingly heavy electrical loads. The entire device contains no brittle material, such as porcelains, to be broken, and requires no cleaning. Compared to the average 12" corona, which is the efiective static eliminating diameter, this bar will produce a corona more than three times as great. The clamps which support the bar-carrying arms All of non-conduc tive material, effectively hold the bar in the desired position. The eliminator of courseoperates on the induction principle, the electrodes'Z or 52 being energized from the insulated conductor l2, from which they are insulated by the rubber tube I 3, the wire in the cable and the rod l i constituting a single conductor member.

In practice, the magnetic coil enclosed in the casing 3! is included in the circuit of the electric connections for operating the machine Which delivers the paper or the like, which isto be treated by the eliminator. Hence, when the main switch is closed to start the machine, the circuit is also closed to the coil in the casing 37, so that the switch arm 8 is moved to bridge the' terminals 6 and 1.

Having thus described our invention, what we believe to be new is:

1. A static eliminator comprising a hollow exterior insulator bar having an insulated conductor member therein, a tubular insulator sleeve in said bar enveloping said conductor, said barenveloping said member and said sleeve over substantially the full length of the eliminatonelectrodes mounted on the bar and projecting to-the outside thereof, said member projecting from one end of said bar, a head having a recess receiving said end, a boreextending from the inner end of said recess, a metallic lining in said bore into which said conductor is inserted, and a metallic stud in said head extending transversely-of said bore, and connected to said sleeve at its inner end.

2. A static eliminator comprising a head, an exterior insulator bar mounted in one end ofsaid head, the bar having a concluctormember therein and having a plurality of electrodes supported along the length thereof, said bar enclosing said member over substantially the full length of the eliminator, the head having a recess in the side, a sleeve inserted in said recess, said sleeve having a bore with a metallic lining therein, a nut screwthreaded into said lining, a cable attached to said nut, and a connector element in said head inserted into said lining and united to the conductor.

3. A static eliminator comprising a cable having a screw with a flange at one end, the cable containing a conductor which is soldered to said screw, a sleeve, .a shouldered bore therein to receive the cable with the screw abutting the shoulder in the bore, the bore being reduced beyond said shoulder, a metallic sleeve in said reduced portion of the bore having a collar at one end received in the outer extremity of the reduced portion of the bore, the screw being screwthreaded into said sleeve, a head having a recess into which the sleeve is inserted, said head having a bore transverse to said sleeve and a conductive lining for said last-named bore, a conductor element in the head having screw-threaded engagement with said lining at its inner end, and

projecting into the sleeve, the head having a recess concentric with the bore therein, an insulator bar received at one end in said recess, a conductor member in the bar within said lining, electrodes on said bar, and a tubular metal sleeve in said bar enveloping said member between the same and said electrodes.

WILLIAM CHARLES HERBERT.

WILLIAM CHARLES HERBERT, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

